Electrical plug



W. L. SMITH.

ELECTRICAL PLUG.

APPLICATION FILED AuG.so. IeI.

UNITED STATES PATENT OFFICE.'

wann I.. sxrm, creme nnnolsco. cnmronmn y ELEGTLBJCAL PLUG.

To all whom z'may concern-i: I'

A Be it known that I, WEBB L. SMITH a zen-of the United States,residing at the city and county ofy San Francisco andState of Caiitornia, have invented new andv useful Improvements in ElectricalPlugs, of which the following is al specification.

This invention relates tog-an. lelectrical plug, and particularly pertains tol af plug adapted to be used vitlrextensioncordsfor domestic- ,urposes."v

One oft"` e' most common objections to elec'-A trical-plugs used in connection. with irons,

` 'tioned.

electric cooking utensils and other devices of a porta-ble nature has been that Athewire'and plug are bound againsttwisting movement,

and it is well nigh impossible to handle a.

portable electric device withouttwisting the cord. At'times it often occurs that the Wires are' brokem It is the principal object of this invention to provide an electrical plug which willy insure constant contact between the various conductors. and. at the same time will allow the -cord to rotate .and twist as desired without being held. ,againsty movementv of the plug.

The present invention contemplates the use of an outer cap which is detachably positioned upon a threaded 'sleeve adapted to combine `with the cap .to hold the porcelain body member in place. This last named membefr is so designed as to rece-ive the connections from the extension wire and to properly contact them with the socket into which the sleeve is screwed. at lthe same time allowing the porcelain. and the wires to rotate within the sleevewithout interruption of the passage of current throughout.

,The invention is illustrated by way of example in the accompanying drawings in which- Figure 1 is a view in side elevation disclosing the completely' assembled plug and a portion ofthe extension wire carried thereby. v

Fig. 2 is a. view in longitudinal section and elevation illustrating the various vital 'elements of the plug and their relation to each other, and further indicating by dotted lines a socket into which the plug may be posi- -Reterring 'more particularly to the drawings, 10 indicatesa cap cylindrical in section and having an end through which a wire opening 11 is formed. The cylindrical portion :of the cap is provided withan annular `V`Siieducation of Letters I Paten-t.

formed to extend cap `en d.'This thread adapted to receive a erably made of pressed metal I i l p y Patented Feb.3,192`o. .iAppnmioamedaagustso,191s.' serialnazsz'gom l l Q *A .i shoulder'12 at which pointas'crew thread is outwardly to the opened and shoulder are' i i' 'i metallic sleeve 1.3 pref as .commonly designed. .Due to the fact that the' cap .is

made ot' dielectric material, the sleeve will be `threaded therefromand will act to Secure a yporcelain body member 14 fin position bei tweenfanouter.fiange of the sleeve and the opposite end ofrthe cap.y This .porcelain .member has an enlarged cylindrical body portlon substantially conforming tothe in.' .nercdiam'eter of the sleeve and a Vreduced cylindrical body end of the lbody portionwand terminates `atv the-shoulder thereof.

fio portion extending. outl lwardly vthrough an openingpinthe-end of K 1G extends entirel)v through the bodypor the other and termi-r .natosat the .outer reducedjface thereofs"4 This last named passageway receives an elec-y tricconductor 17 whichis fastened Ona-ther tion from one end'to end of the plug by a combined binding and contact screw 18. The passageway 15 rece-ives a conductor 1'9 which extends outwardly and engages a' metallic contact ring 20. This ring circumscribes' the reduced portion of the porcelain 'member and rests uponthe shoulder .formed by the enlarged portion of this member. The ring is furthermore held in position on this Shoulder by the. end fiangeof the sleeve 13 and is thus x 1n `continuous sliding contact therewith.

Due to the designA of the device the sleeve 13 will strike the shoul er upon 'the cap to hold its end flange in spaced relation Ito the shoulder-on the porcelain and to properly Vclamp the ring Vbetween the shoulder and thcviiangc without binding the porcelain mennber, and thus permitting it to -rotatewithin the sleeve and the cap. .f a

In operation the device is assembled by first securing the Wires 17 and 19- infixed l relation to the screw 18 and the ring- 20, re-

spectively. When this has been done the sleeve is positioned over the shoulder portion of the cylinder and thereafter the cap is slipped over the sleeve and tightened. In this assembled position the plug may beinserted into a socket and screwed intoplace by the; threads upon the sleeve. Then located properly within the socket the sleeve and cap will be held against movement rela- A second. passageway so; fr

tive thereto, andthe socket and wires may be turned as desired. It 'will thus be seen that an electrical plug is provided which is composed of'very few parts, easily lformed,

5 andreadily assembled, thus insuring that an unskilled person mafy repair the plug should contacts become broken.

It will further be seen that when in opera.-

tion the r.extension cable will be held in a .'na'iner to permit it to` rotate without twistin andwithoutthe possibility of breakage.

Vhile I have shown the preferred form of my electric plug as now known to me, it will be'understood that various changes in the 15 construction, combination and arrangements of parts may be made by those skilled in the art without departing from'the spirit of the invention as lclaimed.

Having thus described my invention, what I claim and desire to secureby Letters Patent is: I

. 1. An electrical connecting plug, including a body member having a reduced outer end ,forming a shoulder with the inner end,

.25 a hollow cap member into which the larger end of the body 1s insertlble, sald cap having' an annular interior shoulder, a spira'lly threaded Contact member adapted to screwvv into co-aetinpj threads in the cap, to lock against the interior shoulder, sald member havlng an inturned flange, and a Contact ringjon the body shoulder with which sai( flange turnably engages. f

2. Anelectrical plug including a cylindrical bod/ v member formed ot' dielectric materlal and having an outer part'of reduced diameter to provide a shoulder, wires in saidl body me1nbe1', .a terminal at the end Ao1 the body member for one of the conducting wires, a terminal ring restingl upon the shoulder of the body member and adapted to be engaged by the opposite wire. a threaded sleeve fitting over the` enlarged portion of, V,

the body member and turnable to be in con-` tinuous contact with said terminal vring..andI Y ay cap engaged a-nd turnable with -the plug y and with relation to the body member.

interior shoulder against which the contact sleeverls lnnnovably locked, and a conducting ringr in. sl i din, contact withthe flangel of the sleeve. y i

In testimony whereotl I have hereunto set my hand ln the presence ot two lsubscrllung wltnesses.

, I WEBB L. SMITH.

Witnesses: y

D. WILLIAMSON,

, CHESTER WILLIAMSON.

pass, said cap haviing` a spiral thread and an 

